Reb Eliezer – a small, but, I think, important adjustment:
I don’t have the Klei Yakar with me at the moment, but if I remember correctly, his point was more about avoiding ostentatious displays of wealth than about the jealousy itself.
For people who do not work on their character (which includes the vast majority of humanity), jealousy is a normal emotion, especially when other people flaunt their riches. We cannot control the natural tendencies of the masses.
What we can control is our own behavior. The Klei Yakar interprets the Pasuk as advice for surviving Galus: Don’t incite the jealousy of the other nations.
The Klei Yakar is not saying, “the other nations persecute us because they’re jealous.” This would be a statement of an irrevocable fate.
He is giving us guidance for how to deal with exile: “If you don’t want the other nations to bother you, make sure not to poke them in the eye.”
Now if only we would listen…